Axiometer.



O. M. HAYNES.

AXIOMETER.

APPLICATION FILED NOV. 3, 1910.

996 ,0 1 7 I Patented June 20,1911.

2 SHEETS-SHEET 1.

2% plum jg.,j f 17 wi tue-ooe'o G. M. HAYNES.

AXIOMETER. APPLICATION FILED NOV. 3, 1910.

D Patented June 20,1911

2 SHEETS-SHEET 2.

. To all whom it may concern:

UNITE s'rarns rgrnn'r orat on.

CHARLES IVL'HAYNES, or cHrLLicornn, OHIO.

. AXIOMETER.

Specification of Letters Patent. P gmented June 20 1911 "Applicationfiled November 3, 1910. Serial No. 590,417.

Optician, in order to ascertain whether or not the prescription has beencorrectly filled. A number of devices have been proposed for thusfinding the position of the axis, that is,

the angle which it makes with the horizontal or the vertical diameter ofthe lens, but the devices which I have been able'to find on the markethave all possessed defects or limitations which militate seriouslyagainst their accuracy or their convenience of manipulation.

It is accordingly the chief object of my present invention to provide animproved device, which may be aptly termed an axiometer or axis-finder,whereby the angular position of the axis can be found readily and withall necessary accuracy.

A further object is to provide in a device for this purpose means forholding and centering the lens, without at the same time subjecting thelens to undue pressure or stress such as would be liable to causechipping or breakage of the glass.

Another object .is to simplify the construction generally, so thatadurable device, of minimum liability of derangement, can be produced atlow cost.

To these and other ends the invention consists in the novel features ofconstruction and combinations of elements he rein-. after described.

It will be recognized by those skilled in the art that the invention canbe embodied in a variety of structures, but of these embodiments I haveselected for illustration and specific. description herein the one whichat the present time I consider to exhibit the various features of theinvention in their most convenient and efi'ective form, This embodimentis shown in the accompanying drawings, in which- Figure 1 is aperspective view of the complete instrument. Fig. 2 1a front eleva-,tion of the lens-holding device and the raduated circle on which theposition 0 the axis is read. Fig. 3 is a cross section on line 3-3 ofFig. 2.

In its preferred form thejinstrument consists essentially of; threeparts, namely, a lens-holding and centering device and a graduatedcircle, the two being combined in the part designated generally by 10; asight ing device 11, in front of the lens-holder,

having a relatively small sighting aperture 11 and a target or indexcard behind the lens-holder, having on its front surface horizontal andvertical lines 13, 14, the two crossing at the precise point where theline of sight from the sighting aperture through i the center of thelens strikes the card; the

part-is nam'e'd being adjustably mounted on a supporting bar 15 and soproportioned that the said line of sight will be per en-' dicular to thelens and to the index car or target. otally mounted on a rod or tube 16telesco ing in a tubularstandard 17 on a suitably This supporting bar isitself pivweighted base 18. By means ofthe thumbscrew 19 the supportingbar 15 can be secured in any position of pivotal adjustment, and bymeans of a set screw 20 the rod 16 can be secured to any desired height,as may suit the convenience of the user. The supporting bar 15' issquare or of knife-edge form in cross section, as shown, and thearts-supported by the same are mounted t ereon by means of sleeves 21,22, 23, of corresponding form so that the parts referred to will alwayshe upright. The supportin sleeves are slidable on the bar, to space heparts properly, and-are provided with setscrews 24, 25, 26, by which thesleeves and the elements carried thereby may be securely fasten'edinadjusted position.

The sighting device is simply an upright plate of sheet metal, with adisk-like top inwhich the sighting aperture ll is tformed, the aperturebeing'encircled by a short concentric shadetube or flange 27 on thefront of \the disk.

'f l he index card 512. of card looard, cellu- I in front witharc-shaped firmly attached to the adjustable carrying sleeve 22.Attached to or integral with the circle and extending inwardly andhorizontally are two wide, arms 32, 33, provided uides 34, 35,concentric with the graduated circle, and rotatably mounted on the armsbetween the guides mentioned is a lens-carrying element in the form of afiat annulus 36, concentric with the said circle, the, annulus beingrefingers 37 extending over its edge from the guides 34, 35.

On the front of the annulus 36, on opposite sides of its center and atequal distances therefrom, are two parallel rails 38, 39, and

on the two rails two lens-clamping members 40, 41 are slidably mountedby means of tubular slides 42. These lens-clamps or clamping members arecurved, being concave toward the center of the annulus, so that onlytheir arms will, when the device is in use, extend inwardly beyond theannulus, the object being to cover or screen as little as possible ofthe central opening. The lens, shown at 4:3, rests against these arms,and is -held.thereon by four forwardly extending studs 44, so arrangedthat the line joining each stud with theother stud on the same clampingmember isperpendicular to the rails. In other words the upper and lowerstuds lie in lines perpendicular to the paths in'which they move. Theresult is that with a eircular'or a symmetrically oral lens if eitherstud is in contact with the edge of the lens the other stud 011 the sameclamping member will also be in contact with the lens edge when thelonger diameter is parallel with the rails 38, 39. Consequently, if bothclamps are moved inwardly the same distanee, into engagement with thelens-edge, the lens, if not alrehdy in the center of the annulus-withits longer diameter horizontal, will be moved to right or left, as thecase may be, and turned in its own plane in one direction or the other,and will thus be brought to the desired central position, with in.longer diameter in close parallelism with he rails, For the purpose ofthus shifting the clamps equallyI provide a pair of curved actuatingarms 45, 46, the upper ends of which pass loosely through slotted lugs47, 48 on therear fares of the clamps, while shifting the associated andits clamp must, by reason of the two their lower ends are fulcrumed atpoints, on the pivots 4:5), 50, fastened to the annulus 3G. Concentricwith these pivots and fixed to the clamps are two intermeshiug gears'51,52. It will therefore be seen that if either arm be moved on its pivot,thereby clamp, the other arm gears, have an equal movement in the opposite direction; These arms are urged yieldingly toward the center of theannulus, and

their free ends bent forwardly, so that by pressing the-same together heclamps will be separated equally, against the light tension of thespring 53.

As previously stated, the annular lens-carrier 36-is rotatableconcentrically with the graduated circle 30. For the purpose of reading01f the angle through which the carrier is turned in using theinstrument the carrier is provided with one or pointers 56 extendinginto the graduations on said circle.

The operation of the instrument is as follows: The lens-clamps 40, i],being opened by pressing the finger pieces 54, together, the lenswhichis to be tested is placed between the elamps with its longerdiameter approximately parallel to the rails 38, 39 and preferably withthe outer side of the lens, .that is, the side facing out when the lensis worn, next to the target. The finger pieces are then releasedallowing the spring 53 to bring the clamps gently against the edge ofthe lens, thereby positioning and centering the same as previouslydescribed. Bringing the longer axis of the lens to the horizontal, byturning the lens-carrier 36 till the proper index 56 points, to zero onthe circle 30, the operator observes thetestlines 13, 14, through. thesighting aperture 11 and the lens. If the lens has no cylindricalsurface, or if the axis of its cylindrical surface is parallel to eithertest-line, no'distortion of either line as seen through the lens will beobserved; but if the axis of such surface is not parallel toone line orthe other such portions of both lines as are seen through the lens willappear to have undergone a partial rotation about their proximity toadjacent with them the two lens-clamps, by a light spring 53. Extendingdownwardly from thearms are two finger pieces 54, 55, having point ofintersection, thereby causingthe lines to appear broken at the edge ofthe lens. The operator now'turns the lens carrier until the portions ofthe lines seen through the lens are brought into, coincidence, oralinement. with theportit ns seen outside the lens... The axisof thecylindrical surface is now parallel to one orth'e other of the testlines which the 'lens has zero position of the to be turned from theindexes 56 to produce and the angle through such parallelism isindicated on the circle 4. In an axiometer, the combination of a 30.This angle is the one which the operator in testing the lens desires tofind, namely, the angle between the axisof the cylindrical surface andthe diameter selected as the basis of measurement. If the lens hasalso aspherically curved surface the latter may be neutralized by placingagainst thelens which is to 'be tested another lens having a sphericalsurface of the .same focal length but opposite curvature, but having nocylindrical surface; that is, a plane-convex or plane-concave lens, asthe case may be. If the focal length of the spherical surface 'of thelens which is to be tested is not known it can of course be readilyfound by means of an opticians spherometer.

As previously stated, the instrument herein specifically described ismerely the preferred form of the invention, which may be embodied inother forms without departure from its proper spirit and scope asdefined by the appended claims.

-What I claim is:

1. In an axio-mete'r, the combination of a rotatable carrier,lens-holding mechanism mounted on the carrier, yielding actuating meansassociated with said mechanism to cause thesame to engage the lens andbring .the center of the lens into alinement with the axis of rotationof thecarrier, manual means for actuating said mechanism to release thelens, a circular scale and an index associated with the carrier, and atarget having a test-line in position to be observed through the lensand outside of the lens simultaneously.

2. In an axiometer, the combination of a rotatable centrally opencarrier, a rail mounted on the carrier and extending translng meansconstantly urging the clamping members slidably mounted on the rail,yielding means constantly urging the clamping members toward the axis ofrotation of the carrier, manual means operable against the tension ofsaid yielding means to shift" the clamping membersoutward, a circularscale simultaneously, one of said elements being rotatable and acircular scale and an index associated with the rotatableelement.

centrally open carrier, lens-clamping members mounted on the carrier andmovable transversely of the carrier in alined paths,

movable arms connected with the respective clamping members,intermeshing toothed elements connecting the arms -,together whereby themovements of the clamping members are made equal in extent and oppositein direction, and yielding means to urge the clamping'members towardeach ot er.

'5. In an axiometer, the combination of a centally open carrier,lens-clamping members mounted on the carrier and movable transverselythereof in alined paths, movable arms connected with the respectiveclamping members to actuate the same, inter-meshing toothed elementsconnecting the arms together whereby the movements of the clampingmembers are made equal in extent and opposite 111 direction, a springar- .ranged to urge the said arms toward each other, and manual meansfor separating the arms against the tension of the spring.

6. In an axiometer, the combination of a centrally open carrier, agraduated circle constituting a support for the carrier, in which thecarrier is rotatably and concen trically mounted, lens-holding andcentering mechanism on the carrier and rotatable therewith, a supportingbar on which the graduated circle is slidably mounted, a target having atest line, slidably mounted on the supporting bar behind the said circleand carrier, and a sighting device mounted on the supporting bar and infront of the circle and carrier and having a sighting aperture.

7. In an axiometer, the combination of an annular carrier, arc-shapedsymmetrical lens-clamping me1nbers movable transversely of the carrierin alined paths, yielding means urging the clamping members toward eachother whereby to grip yieldingly a lens placed between them, and

manual means for separating the clamping members to release the lenstherefrom.

S. In an axiometer, the combination of a centrally open carrier,transverse parallel rails mounted on the carrier, lens-clampingandmanual means for separating the clamping members to release the lenstherefrom.

' 9. In an axiometer, the combination of a rotatable lens-carrier, anon-rotatable graduated circle constituting-- a support ..-fo.r" thecarrier,=-a pointer mounted on the carrier and coiiperating with thegraduated circle, a tarthe targ0t-holder, and the/sighting deviceget-holder behindv the 41ens-carrier, a tarare adjustably mounted. 10get removably.mounted in said holder and In testimony whreof I zufix mysignature having a fest line in position to be closer-(ed in thepresence of two subscribing Witnesses.

through the lens nndoutside the lens silnul- I CHARLES M. HAYNES.tunoously, 21 sighting dance in front of the VltneSses: 1e11s-(.-n1-rier and havmg a slghtlng aperture, WILEY G. HYDE,

and a support on which the graduated circle, HAZEL C." HOUGI-I.

